The study goes on to say that the findings revealed the following about the emissions of e-cigarette: a) besides glycol (the main ingredient), nicotine, flavors, tobacco-specific nitrosamines, volatile organic compounds, acetone, formaldehyde. acetaldehyde, benzo(a)pyrene as well as silicate and various metal particles are present, and b) the particle size is between I00 and 600 nanometers, which is comparable to the particle size found in tobacco smoke of conventional cigarettes. The levels of most harmful substances are lower in thee-cigarettes than in conventional cigarette smoke, but they do accumulate in indoor air.
http://www.newssum.com/e-cigarettes-contain-formaldehyde-and-toxic-199
All companies that make the nicotine combination have their own way of doing it, so the cartridges are not all alike. The one I get makes the nicotine liquid in America.
One would have to know exactly which combination the German group studied. If they didn’t study those made in America, then the study is faulty.
What brand of batteries did they use? I imagine if you get imports of batteries and e liquid from China you might find some of that. I bet the tobacco companies funded the research.